Soybeans (Glycine max L. Merr.) are a major cash crop and investment commodity in North America and elsewhere. Soybean oil is one of the most widely used edible oils, and soybeans are used worldwide both in animal feed and in human food production. Additionally, soybean utilization is expanding to industrial, manufacturing, and pharmaceutical applications.
Phytophthora is a major soybean fungal pathogen that induces stem and root rot in infected plants, causing severe losses in soybean viability and overall yield. Phytophthora root rot is caused by a pathogenic infection of Phytophthora sojae. Resistance to Phytophthora infection is conditioned by naturally occurring variation at the Resistance to Phytophthora sojae (Rps) loci. As races of Phytophthora in the fields shift, previously effective resistance sources are breaking down, causing damage and compromised yields in grower fields.
There remains a need for soybean plants with tolerance or improved tolerance to Phytophthora infection and methods for identifying and selecting such plants.